The hottest metal processing and forming tool with

2022-10-15
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High strength metal forming tools

there is no high-strength steel. There is no high-strength tool

if people encounter the word "steel", it is like meeting the word "high strength". In the market, especially in the automotive industry, the demand for high-strength steel is becoming stronger and stronger, and better performance and economy are needed. However, the wear during processing is relatively serious. How long is the service life of the conventional cutting tools for processing high-strength steel? Although these tools usually have expensive coatings on their surfaces, their service life is not long enough. Until the use of new tool steel can ensure that the tool has a more economical and long service life. For example, the "integrated coating" on the tool can continue to be used for machining after heat treatment

in order to continuously reduce the weight of the vehicle, it is necessary to put forward more and more new requirements for the tool manufacturing and vehicle production process. Metal processing requires the use of new high-strength materials and innovative cutting tool solutions, so as to achieve a controllable and affordable production process. For example, if people compare the proportion of high-strength steel plates used in the new and old Volvo S40 cars, this can be clearly understood. The previous generation of S40 cars used a total of 36.4% of high-strength steel plates, and the rest were conventional steel plates. Although the proportion of high-strength steel plates used in the new generation of s4o cars is reduced to 31.3%, the proportion of ultra-high strength and ultra-high strength steel plates used has reached 22.8%. In other words, the proportion of high-strength steel plates used in the new generation S40 cars has reached 54.1%. However, it should be pointed out that so far, there is no unified definition of high-strength steel plate and ultra-high strength steel plate. The most common definition is based on the standard jointly issued by Volvo automobile company and SSAB. According to this standard, the strength of high-strength steel plate should be 340 ~ 60ompa, the strength of ultra-high strength steel plate should be 600 ~ 800MPa, and the strength of ultra-high strength steel plate should be at least 800MPa. Processing these steel plates means facing many new challenges. In order to process new high-strength steel, we first need to apply higher pressure on the press and change the design of the cutter accordingly. At the same time, the "feed" speed of the tool should be increased in order to reduce the number of stations and improve economy. In addition, reduce the use of "dangerous" lubricants, or simply stop using lubricants completely

the investment in metal forming and processing tools usually exceeds the investment in the machine tool to which the tool belongs. When forming and processing high-strength steel plates, as long as the correct tool materials are selected, the cost can be better reduced

when people seriously consider forming tools, they need to greatly improve the friction, cutting force and forming processing force, which will produce high pressure on conventional steel villages in the process of forming. Statistics on the use of steel for cutting tools show that 1.2379 steel has been mainly used in the past decade; Powder metallurgy can be used in occasions with high quality requirements, and the most commonly used is 1.3344pm. But can these two materials process high-strength steel plates economically

the answer is very complex. We need to consider the relationship between the processing batch and the geometric dimensions of parts, because high-strength steel puts forward new requirements for tool manufacturing, that is, an innovative material coating that is easy to form is needed to verify the performance of the material used in tire production, which can prolong the service life of the tool. Only through continuous "debugging" of the tool can we obtain the tool A new "system" for better matching between lubricants and workpiece materials. Although this system can be used in many occasions, it cannot be used as a widely used problem solution. Even if the latest engine is installed in Volkswagen Golf, it is impossible to win the formula F1 car race, because this car will always be Volkswagen Golf and will never become a racing car, although Volkswagen Golf is undoubtedly a very excellent model in its level. When talking about the forming and processing of ultra-high strength steel plate and ultra-high strength steel plate, it is like talking about the F1 competition of tool manufacturing industry

in addition, it should be noted that coating can only be used as an optimization means to improve tool performance at any time, and the manufacturing process of coating needs to increase relatively large investment. Of course, cutting tool materials that do not need coating can be provided on the market. For example, the Swedish tool manufacturer UDDEHOLM () uses this material that does not need coating to produce "vaneron 40" tools, which can double the overall economy of the processing process, because removing the old coating, grinding, polishing, making a new Xu layer and other processes will produce additional costs

what possibilities can knife manufacturers provide when dealing with new requirements? Standard steel 1.2379 (D2), which is used to process high-strength steel plates, has two main causes of failure: cold surfacing (chip buildup, adhesion wear) and cutting edge cracking (fatigue damage). But there are different solutions. Appropriate processing methods must be developed for different situations, because such factors as part complexity, processing batch, tool size and other decisive factors will affect the tool. Other support should be provided in this regard

nowadays, the generation of cold surfacing can be controlled by means of coating technologies such as PVD, CVD or TD, because the friction between the tool surface and the workpiece material can be reduced in the case of coating. The disadvantage of this technology is that it cannot process any geometric dimension. In addition - as already mentioned, it is necessary to "maintain" the coating, which will also incur a large cost. Therefore, it is necessary to develop a steel without coating after the transformation of the control system

avoid rabbit splashing, punching boast, etc. you'd better know in advance that the characteristic parameters of the curve work are often used as the standard to measure the reaction of tool steel against splashing. This drawing takes four tool steels as examples: orange is caldie, dark blue is Vanadis 4 extra, gray is vancron 40, and light blue is conventional tool steel 1.379. The horizontal axis coordinate is Rockwell hardness, and the vertical axis is the working reaction force of stamping and bending

hard materials will be integrated in tool metal

people now talk about an integrated coating. The idea is to add a separate processing procedure in the production of powder metallurgy tool steel, and add nitrogen into the tool steel, which has a similar effect to carbon rope. In this way, carbonitriding bodies can be obtained instead of carbides; Compared with carbide, its advantage is that this material has a "ceramic property", higher hardness and stronger adhesion resistance. At the same time, this material also has a special surface characteristics similar to the coating. Due to this special surface characteristic, the lubricant can better adhere to the tool surface and reduce the occurrence of adhesion wear. Many experiments have verified the effect of this material, and its application range can range from ultra-high hardness steel plate to very wear-resistant nickel die. The tool material with integrated Xu layer can not only reduce the cost, but also have many other advantages. The size of the tool made of this material can be changed after heat treatment (while the conventional coating is not allowed to carry out dimensional processing after heat treatment), and its surface can be polished to improve the surface quality. In addition, the integrated coating will not crack, so production will not be interrupted

good results: as an example of sheet metal parts, the double acting clutch (left picture) produced by herzing+schroth company (), the pressure gauge housing (middle picture) and oil tank filler (right picture) produced by wemers Schmid company (), the current tool steel not only has high quality assurance, processing capacity and good manufacturability, but also can ensure the minimization of tool wear

the fatigue phenomenon caused by the use of the tool substrate surface can reduce the cracking of the cutting edge. This is also the reason why conventional coating can not solve all the problems arising from the processing of high-strength steel plates alone. The properties of the base material are decisive. Only in this way can the whole tool achieve high ductility and compressive strength. Next is the wear resistance of cutting tools, which is of great significance for mass production. Therefore, in terms of tool material, we have found two solutions at present. If it is only related to the problem of ductility, a material called "caldie" produced by UDDEHOLM using the "high voltage electroslag process" (Desu) is the first choice to solve this kind of problem. The ductility of this metal is higher than that of powder metallurgy steel with low alloying degree. Manufacturers can achieve higher ductility by improving the chemical combination process of steel that will cause too high cost. From the perspective of metallurgy, the caldie material of UDDEHOLM company is a combination of tool steel. Of course, this material should have high wear resistance. In this regard, both schemes are ready to continue to develop the existing "Vanadis 4" steel into the steel code named "Vanadis 4 extra". This material has a combination of characteristics suitable for the forming and processing of high-strength steel plates. This kind of tool steel has high ductility, good compressive strength and slight wear; It not only has high strength, but also has advantages in many feature combinations

both steels can be coated, which can meet different special technical requirements. Considering that the material can have high fatigue strength, the coating processing still has high overall economy

in general, technologically advanced molding workers and their manufacturers can meet the set giant standard of "processing high-strength steel" as much as possible. In this process - usually in cooperation with steel enterprises - they can provide complete material solutions for different applications

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